[Request]: strange doc comments about machines versus containers

### Feature or enhancement request details

The `container machine` documentations talks about filesystems and init:

"each machine keeps its filesystem and runs the image's own init system"

But a container _also_ keeps its filesystem, and it can use the `--init` flag?

So there is no major difference between the two, it's more of a convenience...

The real difference is in the user setup and in the default volume mounts:

"Host integrations such as automatic user and home directory sharing"

----

Talking about `container machine` versus `container` here, not about containers.

Otherwise it would be more about reusing the old kernel, vs starting a new one...

A container machine (with user and home) is usually referred to as a "toolbox".

And you can run those on top of `container machine` (or `container`), if needed:

* Toolbx

* Distrobox

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